Anti-MRSA activity of alkyl gallates

A series of alkyl gallates (3,4,5-trihydroxybenzoates) was found to show antibacterial activity against Gram-positive bacteria including methicillin resistant Staphylococcus aureus (MRSA) strains. For example, dodecyl (C12) gallate (1) exhibited bactericidal activity against MRSA ATCC 33591 strain with the minimum bactericidal concentration (MBC) of 25 μg/mL (74 μM). The time–kill curve study showed that dodecyl gallate is bactericidal against this MRSA strain. This bactericidal activity comes in part from its ability to inhibit respiratory electron transport systems. The length of the alkyl chain is not a major contributor but plays an important role in eliciting the activity.